Go start a discussion about the hardest styles of beer to brew, or just recall the last time you were reading / talking about the subject. You know what people always say? They say: "A pilsner, or some kind of light lager." There's some pretty sound logic behind this answer — such a light, neutral-tasting beer will allow any and all imperfections to shine through. Fair enough, that's certainly true. However, I'm inclined to give the crown for "hardest style of beer to brew really well" to Berliner Weisse.

How many times have you had a truly exceptional, complex-yet-drinkable Berliner? I can think of a handful, maybe, plus another handful of "pretty good" Berliners, and then a lot of average to mediocre examples. Now, I could say the same about many other styles of beer, but the significance of failure when brewing Berliner Weisse is far more serious than with most styles. With one method, it may just not come out sour enough. With another, it may smell like a delightful mix of farts and vomit. Oh, but your pilsner has too much diacetyl? I'm very sorry to hear that.

It's a difficult style to brew for a number reasons, and there are a number of reasons because, well, there are like a million different approaches to brewing Berliner Weisse. It may seem innocent on the outside — this sessionable, low-ABV refresher with straightforward acidity and not a lot of funk — but the deal you make with the devil to achieve that quick, straightforward sourness is a willingness to accept that things might go horribly wrong (or just horribly blandly).

Let's break down all the strategies brewers have employed to create this tricky little thirst quencher:

1. Pure Strain Lactobaccilus and Pitched Yeast1a - By obtaining pure-strain lactobacillus, a brewer can mash as usual, boil for whatever time they see fit, and then pitch pure lacto. As the lacto will not be competing with other bacteria (namely those which produce unpleasant fecal / vomit smells), there is little chance for this to go disastrously wrong. Yeast can be pitched at any time. However, the disadvantage to this tactic is that many report poor results with commercial lacto strains, and are unable to achieve the desired levels of sourness.

1b - Same lacto fermentation as 1a, but Brettamyces can be pitched in place of Saccharomyces, or alongside it. (Both major yeast companies also sell a "Berliner Weisse blend" that already contains this mix). This strategy may result in more funk, with added complexity, but in most cases will not significantly affect level of sourness.

2. Sour Mash and Pitched Yeast2a - Sour mash to acidify some portion of the wort, followed by a boil to pasteurize the wort, followed by a pitch of yeast or Brett to complete fermentation. This is probably the most traditional method of Berliner Weisse production. The sour mash can encompass all of the wort or only a portion of it, and can last for a day up to a week, all depending on your desired level of sourness. The disadvantage of this method is that it's unpredictable, and the most susceptible to horrid off flavors resulting from various bacteria, including the dread Clostridium genus of bacteria. (If you don't believe me about the offensive smells potentially produced here, Butyric acid, which Clostridium butyricum produces, has been used in stink bombs to disrupt Japanese whaling crews, according to Wikipedia. I would not imagine whaling crews smell very good to begin with). Lacto performs well in a hot (90- 115 F) and anaerobic environment, but excess oxygen is an invitation to pukey smells. Of note: many report that these off-flavors are partially scrubbed out during the boil, so the end result may still be a drinkable beer.

2b - Sour mash, followed by no boil, followed by pitch of additional yeast. This method often still involves raising the temperature for long enough to mostly pasteurize the wort. Effectively the same as 2a with less time allowed for pasteurization. If one elects to neither boil nor pasteurize, the opening for off flavors is raised considerably.

2c - Sour mash, followed by boil, then pitching yeast plus additional pure culture lacto. This method allows for the complexity and sourness of a sour mash (including its potential downsides), the safety of boiling the wort to pasteurize it, and the controlled fermentation of a pure strain pitch. By pitching pure lactobacillus alongside yeast, further sourness may be achieved that the sour mash was not able to accomplish. The main fallback of this method is that it is, perhaps, over-complicated, and a hybrid of methods which we have already established may fail or succeed on their own.

Lactobacillus starter.

3. The Bearliner Method - Pitching Cultured Lacto from a Controlled Sour Mash
The method I devised is sort of an amalgamation of the previous methods. My hope was to combine the complexity and natural 'synergy' of a sour mash, but introduce more control over the process. Hopefully. There is something wonderful and zen about fermenting a beer using the same grain that also brewed it, isn't there? I'm sure people have brewed Berliner Weisse using a similar method before, but since I haven't read about it, I decided to name it. Because "Bearliner Weisse" was just too perfect.

My strategy is based on the question: what most frequently sets up a sour mash to go wrong? My conclusion thus far is "O2 exposure" (...mostly). Acetobacter requires oxygen, and while it won't create the most offensive smells in a sour mash, it is generally unwelcome. The Clostridium genus of bacteria — including Clostridium acetobutylicum or Clostridium butyricum — is anaerobic, but grows very slowly in these conditions, meaning it should be overwhelmed by the desired fermentors within a short time.

To build up the numbers of my lactobacillus culture on a smaller scale, and thus give it a firm headstart when tackling the full wort, I began with a low-gravity 2 liter "starter". After boiling the starter wort as usual, I tossed in a handful of grain, topped off with seltzer water to purge oxygen from the 'headspace', and capped with an airlock. Two days later, this little starter was fermenting like crazy, so the culturing was clearly a success. I waited five days for activity to slow, at which point I pulled out the airlock and took a whiff: bready, lemony, citric. With not even a whiff of pukey smells, the aroma was pretty much all I could hope for with this experiment. The next day I got to brewing.

The beer itself made for a very easy brewday, as I only boiled for about 15 minutes, adding a scant quarter ounce of hops at flameout, mostly for flavor and some preservative insurance. I then split the batch between two 3 gallon fermentors. One of them may be dry-hopped with more "Experimental Hop 01210," while the other is going to receive a yet-unmeasured amount of blueberries, because a blueberry Berliner Weisse sounds delicious to me. But, backing up a bit: after cooling down the wort to about 95 degrees F, I split the lacto starter between the carboys and let em rip. And rip they did: I had a vigorous fermentation, with a thick foamy soap-bubble krausen, by the next morning. Whatever sort of lacto (and possibly yeast too?) I cultured from that grain, it's no slouch, that's for sure. Within four days, the gravity was down to 1.012 from 1.037. Two days later, I pitched a small flask of Brettanomyces into each carboy. Six days after that, they are still bubbling intermittently.

My main concern with this method is that I'm not able to ferment the actual beer at 100+ degrees F, which the lacto would really like. Fermenting above 100 F is really ideal for the lacto phase of fermentation, but I lack the equipment to maintain this currently, and merely set the carboys in the hottest closet in my house, wrapped in a few blankets. However, the lacto starter is easy to keep temp with, being small and easily fittable in a mash tun full of hot water.

25 comments:

Same method here, with two small differences:- I ad some lactic acid to the starter to get the pH down to 4,9-4,8 that favours the lactic bacteria even more. (the same is done for sour dough starters, for the same reasons)- I pitch lacto, sacch & brett at the same time.Results varied quite a bit, it all depends on what you catch from the grain.

Thanks for the comment. Smart idea to add lactic acid right to the starter, I'll have to do that next time as well. Do you think you get the same level of sourness adding all the yeast and lacto at the same time, as opposed to giving the lacto a head start for a few days?

Yeah, the main fallback does seem like it'd be the variation, depending what you catch. I thought about saving a portion of the lacto starter so I could pitch the same strain each time, but I don't plan on brewing another Berliner again until next summer. Should be feasible, though.

Well, if you catch the right strains, there is this 'cooperation' between the lacto and yeast, where the yeast consumes the simpler sugars and the bacteria chop up the more complex ones and also leave a bit for the yeast. This as I understand it from some sour dough recources. I hope that leaves some room for the production of lactic acid.

I tend to make the lacto starter bigger than the yeast one and underpitch the yeast as you also catch some(thing) from the grains.

On catching from the grain, check suigenerisbrewing's blog post from august 5, on what he caught,

I have done 2 Berliners this year and have really been crowdsourcing info from as many brewers as possible to dial in my process. One I did earlier this year was soured similarly, except I just tossed a handful of uncrushed pilsner right into the fermenter warm, then added WLP029. That beer was wayyyy too sour, and had a funky aroma that I was able to clean up with some Brett Trois.

I am just not a huge fan of this method, its very difficult to predict what that beer will taste like.

A few things I have been working into mine recently...

-Single Decoction, seems to add a slight malt graininess to the beer.-No boil, so you'll get a little bit of the wild in there as well.-Repitching slurry from previous batches along with a new commercial Lacto vial to start fermentation.-Brett C. it just seems to work really well in these beers. Its not funky, slightly acidic but adds some depth to the beer.

It's interesting that your batch ended up too sour. Honestly my main worry was that I wouldn't be able to get the beer sour enough — it seems to be the common complaint that I hear, and probably the most common issue with many commercial Berliners. But as has been said, it all depends what bugs you happen to catch, and that's sort of a crap-shoot.

I would like to try a decoction next time. I've never done one before and I didn't want to over-complicate this brew-day, but it seems to be the way to go with Berliners. I'll have to remember to save some slurry too.

I had a long talk with the head brewer at Nodding Head brewpub in Philly, during Philly Beer Week. They make a fantastic Berliner, Ich Bin Ein Berliner Weiss, its only brewed from Spring to Fall and he said the first batch is always a little less sour then he wants. But as he repitches his ale yeast and lacto slurry he really dials it in, mid summer he has to start with a new pitch but will add some of the old slurry to ensure consistency.

This method has really worked well for me. Any interest in trading a few bottles and maybe posting reviews on our blogs? A little comparison?

Interesting. I've been to Nodding Head, but I haven't had their Berliner. That sounds like a great method. Unfortunately to utilize it as a homebrewer I guess you'd have to be brewing Berliners regularly. I suppose if this batch of mine turns out nicely, I'll just save the dregs until next summer and see if they still want to do their thing!

I'd definitely be interested in trading. Philly is pretty easy for me to get to, being my home state and all, but I don't make it down there often enough. Maybe we can arrange something in a few months?

I second what Jabien said. That has been my approach this year for three batches of Berliner Weisse. However, I sour the whole wort rather than doing a sour mash to avoid any of the off-flavors or sparging problems associated with sour mashes (temp of grain bed mostly). I find sparging the grain and then pasteurizing the wort at 190F before "chilling" to 120F with warm water through my IWC or plate chiller gets the wort the ideal temp for the lactobacillus, be it a pure culture or an uncrushed grain pitch. Purging the vessel of air with CO2 is very important to achieving a clean lactic sourness. You can also bring the pH of the wort down to around 4.8 before chilling with acid malt or food-grade lactic acid. This helps to preserve the proteins for head retention as the lacto can degrade the proteins at higher pH (this info was found here: http://www.themadfermentationist.com/2012/06/100-lactobacillus-berliner-weisse.html). Many brewers use the Wyeast 3191 blend or a mix of Wyeast 5335 Lactobacillus and Wyeast 1007 German Ale. The blend is convenient but often disappointing in the short term. The sourness just never develops in a predictable way. At the same time, Wyeast 1007 adds little in the way of complementary flavors to the lactic sourness (and it never floccs out!). My favorite yeast for a neo-Berliner Weisse is Brett Trois. So far it is the most complex flavor profile and loves living in low pH wort. Anyone who hasn't read Wild Brews should consider getting a copy. I learned a lot about how to steer sour beers in a desirable direction (control would be too strong a word) with Brett. Much of the low flavor complexity in a Sacch. fermented Berliner Weisse is due to the low OG. Brett provides a lot more flavor despite the limited sugars.

Thanks for the comment! I agree that purging the vessel with CO2 is quite important, and Brett definitely adds a lot of character. I might try only Brett Trois another time, but it was part of the one blend I added to this batch. I'm curious to see how it performs alongside a few other Brett strains.

Hey Derek,The berliner weisse is all finished and bottled - drop me your address to luukinen at gmail and I'll send you a bottle or two. My batch turnaround, including the 5-day starter was 2 weeks, and it's now been in bottle for 2 weeks, so the sourness is very restrained. I also did a version with strawberries and a version with blueberry which I still need to bottle, and they might be a little more tart. Either way it's tasting great and I'm planning to do it again!-Bryan

I don't believe I oxygenated the wort / beer at any point. Same with a gose that I'm doing now. The lacto doesn't need it and the Brett works fine without it, and I'm not counting on a sacch strain for full attenuation.

Great article, just wanted to add that there is another merhod; adding sourdough. The norwegian national homebrewing competition this year was won by a guy who pitched just this: http://www.sourdo.com/cultures/bahrain/It doesn't produce alcohol by itself, but apparently yeast develops from adding the flour in the dough starter.

At that point, it has already cooled down to close to whatever the ambient temperature is (room temp, in most cases), since you're giving the lacto a long lead time. By the time you get around to pitching a second culture to finish it out, you shouldn't need to adjust the temp much unless it happens to be very high for whatever reason. Brett can tolerate pretty highish fermentation temperatures anyway, so anywhere in the 70's range should be fine by the time you pitch yeast.

Curious how long you let the beer go after adding your Brettanomyces. I've done similar methods in the past with pretty good luck, however haven't yet played with Brettanomyces, and from the little I do know so far, seems that I'd want to give more time for character to really start to develop. Thanks in advance for any tips!

Just want to say that I've tried this method (with a few tweaks) and it's tremendous. That starter method is very clever. Tweaks:I went no-boil, mashing at 150F, ramping to 165F, lautering, lowered the pH of the wort to 4.7 before pitching starter using lactic acid. For temp control, I surround the fermentor with insulating foil like this stuffhttp://www.acehardware.com/product/index.jsp?productId=1296204&KPID=986663&pla=pla_986663and control the temp with a cheap heating pad. I fermented in a range between 85-90F.

I just let the all-lacto fermentation go on its own to about 3.2pH as measured with my cheapo meter, took a few weeks. I did a parallel batch of a small German ale, lightly hopped, at normal ale fermenting temps. Blended the two together, let rest at normal ale temps for a few weeks, then bottled.